Qt:当你在一个函数内时如何显示一个Messagebox？

Question

我正在使用Qt Nokia SDK进行开发.

在尝试在函数中显示消息框时,我无法显示MessageBox的按钮.如果我尝试在主窗口中显示它,显示按钮没有问题.

主窗口包含一个包含不同小部件的QStackWidget.

这是在主窗口中工作的代码:

QMessageBox msgBox;
msgBox.setText("Name");
msgBox.setInformativeText("Do you want to save your changes?");
msgBox.setStandardButtons(QMessageBox::Save | QMessageBox::Discard |
                          QMessageBox::Cancel);
msgBox.setDefaultButton(QMessageBox::Save);
int ret = msgBox.exec();

这是我在收到来自Web请求的响应后运行的函数和代码(消息框显示,但不显示按钮.

void MainWindow::RequestReceived()
{
    QMessageBox *msgBox = new QMessageBox(this);
    msgBox->setText("Test");
    msgBox->setWindowModality(Qt::NonModal);
    msgBox->setInformativeText("Do you want to save your changes?");
    msgBox->setStandardButtons(QMessageBox::Save | QMessageBox::Discard | 
                               QMessageBox::Cancel);
    msgBox->setDefaultButton(QMessageBox::Save);
    int ret = msgBox->exec();
}

任何人都知道发生了什么？

提前致谢!

Answer 1

试试这个代码.它会帮助你.

QMessageBox Msgbox;
    int sum;
    sum = ui->textEdit->toPlainText().toInt()+ ui->textEdit_2->toPlainText().toInt();
    Msgbox.setText("sum of numbers are...."+sum);
    Msgbox.exec();

Answer 2

也许这会有所帮助：

QMessageBox::StandardButton reply;

reply = QMessageBox::question(this, "Save", "Do you want to save your changes?",
    QMessageBox::Save | QMessageBox::Discard | QMessageBox::Cancel);

if (reply == QMessageBox::Save) {
    qDebug() << "Yes was clicked";
    // code for saving...
}
if (reply == QMessageBox::Discard)
{
    // toDo
}
if(reply == QMessageBox::Cancel)
{
    //toDo
}

此代码将产生以下内容：

Answer 3

尝试改变这一行：

QMessageBox *msgBox = new QMessageBox(this);

到

QMessageBox *msgBox = new QMessageBox(0);